Dietary inclusion of whole soy foods results in significant reductions in clinical risk factors for osteoporosis and cardiovascular disease in normalpostmenopausal women

Objective: To determine the effects of dietary inclusion of soy foods on cl inical markers for cardiovascular disease (CVD) and osteoporosis in normal postmenopausal women. Design: This was a single open-group prospective clinical intervention. For ty-two normal postmenopausal women consumed three daily servings for 12 con secutive weeks of whole soy foods containing approximately 60 mg/d of isofl avones. Blood and urine specimens were obtained at baseline and after 12 we eks of dietary intervention. Results: Serum and urine levels of individual and total isoflavones increas ed significantly (7-19 fold, p < 0.001) from baseline. A significant increa se (9.3%, p < 0.05) in the mean lag-time of low-density lipoprotein cholest erol oxidation was seen and was positively correlated with serum phytoestro gens (p < 0.05). Significant increases were found in mean levels of high-de nsity lipoprotein cholesterol (HDLc) (3.7%, p <less than> 0.05) and serum o steocalcin (10.2%,p < 0.025). Significant decreases were observed in total cholesterol:HDLc ratios (5.5%, p < 0.006) and mean urinary N-telopeptide ex cretion (13.9%, p < 0.02). Urinary excretion of total isoflavones was negat ively correlated with very-low-density lipoprotein cholesterol, triglycerid es, and total cholesterol: HDLc ratios (p < 0.04). No significant changes f rom baseline in HDLc peroxidation, total cholesterol, triglycerides, low-de nsity lipoprotein cholesterol, very-low-density lipoprotein cholesterol, bo ne-specific alkaline phosphatase, follicle-stimulating hormone, or estradio l levels were observed. Conclusions: Dietary inclusion of whole soy foods containing 60 mg/d of iso flavones results in significant serum levels of phytoestrogens and reductio ns in several key clinical risk factors for CVD and osteoporosis in normal postmenopausal women. Long-term, placebo-controlled clinical trials are nee ded to evaluate the effect of phytoestrogens on the clinical endpoints of C VD and osteoporosis in this population.